Optimum null steering techniques for linear and planar antenna arrays using genetic algorithm

Null steering to cancel interference at a given directions in adaptive arrays could be achieved efficiently using genetic algorithm (GA). Major deviations in the beam steering direction and large perturbation in the side lobe level could be the main limitations for placing nulls in the far field pattern. In this paper, null steering techniques for Dolph-Chebyshev and thinned antenna arrays using GA are studied. Linear arrays composes of 20 and 40 elements are designed. Single, multiple, symmetric or adjacent to the main beam interference scenarios are considered. Various results are presented and discussed to show the advantages and limitations for all null steering techniques. Also, a novel GA/MoM code is implemented to suit any optimization problem involving wire antennas. This new code is used to fix nulls for an example of planar array with (5/spl times/10) short dipole antennas.